Cure Cratering Issues with a GreTan Firing Pin Hole Bushing Job

Craters may look interesting on the moon, but you don’t want to see them on your primers. Certain mechanical issues that cause primer craters can also cause primer piercing — a serious safety problem that needs to be addressed. If you have a gun that is cratering primers (even at moderate pressure levels), there is a solution that works with many rifles — send your bolt to Greg Tannel to have the firing pin hole bushed.

Shooters who convert factory actions to run 6BRs, 6PPCs or other high-pressure cartridges should consider having the firing pin bushed. These modern cartridges like to run at high pressures. When running stout loads, you can get cratering caused by primer flow around the firing pin hole in the bolt face. The reason is a little complicated, but basically the larger the hole, the less hydraulic pressure is required to crater the primer. A limited amount of cratering is normally not a big issue, but you can reduce the problem significantly by having a smith fit a bushing in the firing pin hole. In addition to reduced cratering, bushing the firing pin often produces more consistent ignition.

This is a highly recommended procedure that our editors have had done to their own rifles. Greg Tannel (Gre-Tan Rifles) is an expert at this procedure, and he does excellent work on a wide variety of bolts. Current price for a bushing job, which includes turning the firing pin to .062″, is $80.00, or $88.00 with USPS Priority Mail return shipping.

If you have a factory rifle, a bushed firing pin is the way to go if you are shooting the high-pressure cartridges such as 6PPC, 6BR, 6-6.5×47 and 6.5×47. This is one of the most cost-effective and beneficial upgrades you can do to your factory rifle. For more info on the Firing Pin Bushing process, visit GreTanRifles.com, or email greg [at] gretanrifles.com. (After clicking the link for GreTanRifles.com, Click on “Services” > “Shop Services” > “Bolt Work”, and you’ll see a listing for “Bush Firing Pin Hole & Turn Pin”. Select “View Details”.)

How to send your bolt in to be bushed:
You can send your bolt snail mail, priority mail, or UPS (Please do not use FEDEX as it sometimes has delivery delays). Pack your bolt carefully and ship to: Gre’-Tan Rifles, 24005 Hwy. 13, Rifle CO 81650. Please include your name, phone number, and return shipping address.

Due to the high volume of work, turn around is 5 to 8 weeks on bushing a bolt. Three or more bolts will be sent back to you UPS and we will have to calculate shipping. We can overnight them at your expense. You can pay by check, money order, or credit card. For more information visit GretanRifles.com.